Scan Driving Circuit Potential Voltage Stabilization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing scan driving circuits for thin film transistor liquid crystal displays experience unstable potential voltage at control points connected with multiple TFTs in series, leading to incorrect scanning signals due to the conduction of transistors M2 or M9, which affects the accuracy of scanning signals outputted from scanning lines.
Innovation Solution
A scan driving circuit with cascaded scan driving units, including a first control module, a second control module, and an output module, where the second control module incorporates a first switch unit, a second switch unit, a potential holding unit, and a switch control unit, ensuring that the first and second switch units are not conducted simultaneously, thereby stabilizing the potential voltage at the control points and improving scanning signal accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a control point is connected with multiple TFTs in series to achieve scanning signal control, then the scanning function is enabled, but the potential voltage at the control point becomes unstable leading to incorrect scanning signals
Solution Approach 1:
The control point connection is segmented into multiple separate connection paths with individual switch units (first switch unit, second switch unit) that are controlled independently. This segmentation prevents the instability caused by multiple TFTs in series by creating distinct controllable segments that can be managed separately through their respective control signals.
Solution Approach 2:
A potential holding unit is introduced as an intermediary component between the control point and the scanning lines. This potential holding unit acts as a buffer that stabilizes the potential voltage at the control point, preventing direct interference from multiple TFT connections and ensuring stable scanning signal output.
2Measurement precision
If multiple switch units are controlled independently to stabilize potential voltage, then scanning signal accuracy is improved, but the device complexity increases
Solution Approach 1:
Multiple switch units and their control functions are merged into a unified scan driving circuit structure that shares common components and control logic. The first and second switch units are integrated with the potential holding unit in a coordinated manner, allowing independent control while maintaining overall circuit simplicity through shared architecture.
Solution Approach 2:
The switch units are designed with multi-functional capabilities, serving both as control elements for potential voltage stabilization and as part of the scanning signal transmission path. The potential holding unit also serves dual purposes by both stabilizing voltage and acting as a buffer in the signal path, reducing the need for separate dedicated components.
Data Source
AI summary
A scan driving circuit and a device are disclosed. The scan driving circuit has a plurality of scan driving units coupled in cascade. A (N)-cascaded scan driving unit includes a first control module, a second control module, and an output module. The second control module includes a first switch unit, a second switch unit, a potential holding unit and a first switch control unit. A control end of the second switch unit receives the (N-1)-stage scanning signal, the first switch control unit is configured for controlling the first switch unit, according to the second clock signal, the (N-1)-stage scanning signal, and the first constant voltage signal passed through the second control end of the first switch unit, to control the first switch unit, for operating that the first switch unit and the second switch unit are not conducted at the same time.